A lake with hundreds of ancient skeletons surrounding it. The surprise is what killed them.

L. Frank Baum wrote part of the "Wizard of Oz" series in this wooden Victorian beach resort.

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

The eerie ruins of this feudal fortress witnessed the execution of 60 conspirators in 1387.

A submerged archeological park still holds the wonders of a Roman Sodom.

This sword isn't waiting for a king to pull it out. It was placed there by a saint.

The remains of this castle, known as the Witch’s Eye, watch over the Thur Valley.

This artificial archipelago was supposed to resemble a map of the world.

A cavernous three-story, 43,800-square-foot basement that was forgotten about for 60 years.

An abandoned village that resides along the mountains of the Aosta Valley.

The largest cemetery for enslaved people in Loudoun County was almost lost to history, if not for the research of a minister.

Off-limits and full of venomous pit vipers, Brazil’s Snake Island has a frighteningly apt nickname.

Once a 19th-century brasserie, this McDonald's exterior celebrates Alsatian design and the "King of Beer."

This seaside Italian village doesn't just look Escher-esque, it actually inspired the mind-bending artist.

The remnants of a wooden-hulled fleet built and abandoned in WWI, now home to a thriving ecosystem.

A mountain of conch shells created by centuries of fishermen.

A narrow opening between the mountains of the Amalfi Coast creates a scenic hidden beach.

Beautiful views and Roman-style statues on the Italian coast.

Amalfi's pre-industrial history is slowly being engulfed by the lush vegetation of the Ferriere Valley.

George Martin's Caribbean recording studio now rots within the shadow of an active volcano.

In the basement of the U.S. Capitol Building is a hidden storage room full of ornate floor tiles leftover from the 1850s.

There just so happens to be a court even higher than the U.S Supreme Court: a basketball court in the building itself.

An atomic bomb-proof strongbox protects the U.S. Constitution from terrorists and thieves.